diff --git a/admin/index.html b/admin/index.html
index dd1921f..e735297 100644
--- a/admin/index.html
+++ b/admin/index.html
@@ -142,6 +142,38 @@
       margin: 12px 0 8px; color: #fff; font-size: 14px;
       text-transform: capitalize;
     }
+
+    /* Form fields inside drawer */
+    #profile-form label {
+      display: block;
+      color: var(--text2);
+      font-size: 12px;
+      margin: 8px 0 4px;
+    }
+    #profile-form input[type="text"],
+    #profile-form input[type="number"],
+    #profile-form select,
+    #profile-form textarea {
+      width: 100%;
+      background: var(--bg3);
+      border: 1px solid var(--border2);
+      color: var(--text);
+      padding: 6px 10px;
+      font-size: 13px;
+      border-radius: 4px;
+      font-family: inherit;
+    }
+    #profile-form input[type="checkbox"] {
+      margin-right: 6px;
+      accent-color: var(--accent);
+    }
+    #profile-form textarea {
+      resize: vertical;
+    }
+    #profile-form section {
+      border-bottom: 1px solid var(--border);
+      padding-bottom: 8px;
+    }
     .value-cell {
       max-width: 400px; overflow: hidden;
       text-overflow: ellipsis; white-space: nowrap;
@@ -267,6 +299,8 @@
   sessions(qs='') { return this.get('/admin/sessions' + (qs ? '?' + qs : '')); },
   memory(qs='') { return this.get('/admin/memory' + (qs ? '?' + qs : '')); },
   profiles() { return this.get('/admin/profiles'); },
+  profile(id) { return this.get(`/admin/profiles/${id}`); },
+  saveProfile(id, body) { return this.request('PUT', `/admin/profiles/${id}`, body); },
   session(id){ return this.get(`/admin/sessions/${id}`); },
   delSession(id){ return this.del(`/admin/sessions/${id}`); },
   userSessions(id){ return this.get(`/admin/users/${id}/sessions`); },
@@ -599,7 +633,7 @@
 function renderProfiles(profiles) {
   if (!profiles.length) return '<div class="placeholder">No profiles.</div>';
   let html = '<table><thead><tr>';
-  ['ID','Name','Description','Admin Only'].forEach(h => html += `<th>${h}</th>`);
+  ['ID','Name','Description','Admin Only','Actions'].forEach(h => html += `<th>${h}</th>`);
   html += '</tr></thead><tbody>';
   for (const p of profiles) {
     html += `<tr>
@@ -612,6 +646,7 @@
           <span class="slider"></span>
         </label>
       </td>
+      <td><button onclick="editProfile('${esc(p.id)}')">Edit</button></td>
     </tr>`;
   }
   html += '</tbody></table>';
@@ -622,6 +657,147 @@
   try { await api.updateProfile(id, value); loadProfiles(); } catch (err) { alert(err.message); }
 };
 
+// ── Profile Edit ───────────────────────────────────────────────────────────
+window.editProfile = async (id) => {
+  try {
+    const p = await api.profile(id);
+    showProfileDrawer(id, p);
+  } catch (err) {
+    alert(err.message);
+  }
+};
+
+function showProfileDrawer(id, p) {
+  const existing = document.querySelector('.drawer-overlay');
+  if (existing) existing.remove();
+
+  const modelVal = Array.isArray(p.model) ? p.model.join('\n') : String(p.model || '');
+  const toolsVal = Array.isArray(p.enabled_tools) ? p.enabled_tools.join('\n') : String(p.enabled_tools || '');
+  const subagentToolsVal = Array.isArray(p.subagent_tools) ? p.subagent_tools.join('\n') : String(p.subagent_tools || '');
+  const ctxVal = Array.isArray(p.context_providers) ? p.context_providers.join('\n') : String(p.context_providers || '');
+
+  const overlay = document.createElement('div');
+  overlay.className = 'drawer-overlay';
+  overlay.innerHTML = `
+    <div class="drawer" style="width:600px;max-width:95vw;">
+      <h3>Edit Profile: ${esc(p.id)}</h3>
+      <div id="profile-form" style="display:flex;flex-direction:column;gap:12px;">
+
+        <section><h4 class="group-title">Basic</h4>
+          <label>Name</label><input id="pf-name" value="${esc(p.name)}">
+          <label>Description</label><input id="pf-description" value="${esc(p.description)}">
+          <label>Short Description</label><input id="pf-short_desc" value="${esc(p.short_description||'')}" placeholder="One-line summary...">
+          <label>LLM Backend</label><input id="pf-backend" value="${esc(p.llm_backend)}">
+        </section>
+
+        <section><h4 class="group-title">Model & Generation</h4>
+          <label>Model (one per line, priority order)</label>
+          <textarea id="pf-model" rows="4" style="font-family:monospace;">${esc(modelVal)}</textarea>
+          <label>Temperature</label><input id="pf-temp" type="number" step="0.01" value="${p.temperature}" style="width:100px;">
+          <label>Top-K</label><input id="pf-topk" type="number" value="${p.top_k??''}" style="width:100px;">
+          <label>Top-P</label><input id="pf-topp" type="number" step="0.01" value="${p.top_p??''}" style="width:100px;">
+          <label>Max Iterations</label><input id="pf-max_iter" type="number" value="${p.max_iterations}" style="width:100px;">
+          <label>Num Threads</label><input id="pf-num_thread" type="number" value="${p.num_thread??''}" style="width:100px;">
+        </section>
+
+        <section><h4 class="group-title">Thinking</h4>
+          <label><input type="checkbox" id="pf-think" ${p.think_enabled?'checked':''}> Think Enabled</label>
+          <label><input type="checkbox" id="pf-budget" ${p.iteration_budget_enabled?'checked':''}> Iteration Budget</label>
+          <label><input type="checkbox" id="pf-goal" ${p.goal_anchoring_enabled?'checked':''}> Goal Anchoring (interval: <input id="pf-goal_int" type="number" value="${p.goal_anchoring_interval}" style="width:60px;">)</label>
+          <label><input type="checkbox" id="pf-stall" ${p.anti_stall_enabled?'checked':''}> Anti-Stall (threshold: <input id="pf-stall_thr" type="number" value="${p.anti_stall_threshold}" style="width:60px;">)</label>
+          <label><input type="checkbox" id="pf-validate" ${p.step_validation_enabled?'checked':''}> Step Validation</label>
+          <label><input type="checkbox" id="pf-replan" ${p.adaptive_replan_enabled?'checked':''}> Adaptive Replan</label>
+        </section>
+
+        <section><h4 class="group-title">Planning</h4>
+          <label><input type="checkbox" id="pf-plan" ${p.planning_enabled?'checked':''}> Planning Enabled</label>
+          <label><input type="checkbox" id="pf-plan_mand" ${p.planning_mandatory?'checked':''}> Planning Mandatory</label>
+          <label><input type="checkbox" id="pf-phase1" ${p.planning_phase1_enabled?'checked':''}> Phase 1 (Analysis)</label>
+          <label><input type="checkbox" id="pf-phase2" ${p.planning_phase2_enabled?'checked':''}> Phase 2 (Review)</label>
+          <label><input type="checkbox" id="pf-phase3" ${p.planning_phase3_enabled?'checked':''}> Phase 3 (Plan)</label>
+        </section>
+
+        <section><h4 class="group-title">Sub-agent</h4>
+          <label><input type="checkbox" id="pf-sub_plan" ${p.subagent_planning_enabled?'checked':''}> Sub-agent Planning</label>
+          <label>Sub-agent Think Enabled</label>
+          <select id="pf-sub_think">
+            <option value="null" ${p.subagent_think_enabled===null?'selected':''}>Inherit (null)</option>
+            <option value="true" ${p.subagent_think_enabled===true?'selected':''}>True</option>
+            <option value="false" ${p.subagent_think_enabled===false?'selected':''}>False</option>
+          </select>
+          <label>Sub-agent Tools (one per line)</label>
+          <textarea id="pf-sub_tools" rows="3" style="font-family:monospace;">${esc(subagentToolsVal)}</textarea>
+        </section>
+
+        <section><h4 class="group-title">Tools</h4>
+          <label>Enabled Tools (one per line)</label>
+          <textarea id="pf-tools" rows="6" style="font-family:monospace;">${esc(toolsVal)}</textarea>
+          <label>Context Providers (one per line)</label>
+          <textarea id="pf-ctx" rows="3" style="font-family:monospace;">${esc(ctxVal)}</textarea>
+        </section>
+
+        <section><h4 class="group-title">System Prompt</h4>
+          <textarea id="pf-system" rows="10" style="font-family:monospace;width:100%;">${esc(p.system_prompt||'')}</textarea>
+          <label>Sub-agent System Prompt</label>
+          <textarea id="pf-sub_system" rows="4" style="font-family:monospace;width:100%;">${esc(p.subagent_system_prompt||'')}</textarea>
+        </section>
+
+        <div style="display:flex;gap:8px;margin-top:8px;">
+          <button class="btn btn-primary" onclick="saveProfileEdit('${esc(id)}')">Save</button>
+          <button onclick="this.closest('.drawer-overlay').remove()">Cancel</button>
+        </div>
+      </div>
+    </div>`;
+  overlay.addEventListener('click', (e) => { if (e.target === overlay) overlay.remove(); });
+  document.body.appendChild(overlay);
+}
+
+window.saveProfileEdit = async (id) => {
+  const body = {
+    name: document.getElementById('pf-name').value,
+    description: document.getElementById('pf-description').value,
+    short_description: document.getElementById('pf-short_desc').value,
+    llm_backend: document.getElementById('pf-backend').value,
+    model: document.getElementById('pf-model').value.split('\n').map(s => s.trim()).filter(Boolean),
+    temperature: parseFloat(document.getElementById('pf-temp').value),
+    top_k: document.getElementById('pf-topk').value ? parseInt(document.getElementById('pf-topk').value, 10) : null,
+    top_p: document.getElementById('pf-topp').value ? parseFloat(document.getElementById('pf-topp').value) : null,
+    max_iterations: parseInt(document.getElementById('pf-max_iter').value, 10),
+    num_thread: document.getElementById('pf-num_thread').value ? parseInt(document.getElementById('pf-num_thread').value, 10) : null,
+    think_enabled: document.getElementById('pf-think').checked,
+    iteration_budget_enabled: document.getElementById('pf-budget').checked,
+    goal_anchoring_enabled: document.getElementById('pf-goal').checked,
+    goal_anchoring_interval: parseInt(document.getElementById('pf-goal_int').value, 10),
+    anti_stall_enabled: document.getElementById('pf-stall').checked,
+    anti_stall_threshold: parseInt(document.getElementById('pf-stall_thr').value, 10),
+    step_validation_enabled: document.getElementById('pf-validate').checked,
+    adaptive_replan_enabled: document.getElementById('pf-replan').checked,
+    planning_enabled: document.getElementById('pf-plan').checked,
+    planning_mandatory: document.getElementById('pf-plan_mand').checked,
+    planning_phase1_enabled: document.getElementById('pf-phase1').checked,
+    planning_phase2_enabled: document.getElementById('pf-phase2').checked,
+    planning_phase3_enabled: document.getElementById('pf-phase3').checked,
+    subagent_planning_enabled: document.getElementById('pf-sub_plan').checked,
+    subagent_think_enabled: (() => {
+      const v = document.getElementById('pf-sub_think').value;
+      return v === 'null' ? null : v === 'true';
+    })(),
+    subagent_tools: document.getElementById('pf-sub_tools').value.split('\n').map(s => s.trim()).filter(Boolean),
+    enabled_tools: document.getElementById('pf-tools').value.split('\n').map(s => s.trim()).filter(Boolean),
+    context_providers: document.getElementById('pf-ctx').value.split('\n').map(s => s.trim()).filter(Boolean),
+    system_prompt: document.getElementById('pf-system').value,
+    subagent_system_prompt: document.getElementById('pf-sub_system').value,
+  };
+
+  try {
+    await api.saveProfile(id, body);
+    document.querySelector('.drawer-overlay')?.remove();
+    loadProfiles();
+  } catch (err) {
+    alert(err.message);
+  }
+};
+
 // ── Drawer ─────────────────────────────────────────────────────────────────
 function showDrawer(title, content) {
   const existing = document.querySelector('.drawer-overlay');
diff --git a/navi/api/routes/admin.py b/navi/api/routes/admin.py
index d44aee2..ff92885 100644
--- a/navi/api/routes/admin.py
+++ b/navi/api/routes/admin.py
@@ -281,3 +281,106 @@
         admin_id=user.id,
     )
     return {"ok": True}
+
+
+@router.get("/profiles/{profile_id}")
+async def admin_get_profile(
+    profile_id: str,
+    user: Annotated[User, Depends(require_permission("navi.profiles.manage"))],
+):
+    """Return full profile configuration including system prompt."""
+    from navi.api.deps import get_profile_registry
+
+    try:
+        profile = get_profile_registry().get(profile_id)
+    except Exception:
+        raise HTTPException(status_code=404, detail="Profile not found")
+
+    return {
+        "id": profile.id,
+        "name": profile.name,
+        "description": profile.description,
+        "short_description": profile.short_description,
+        "full_description": profile.full_description,
+        "system_prompt": profile.system_prompt,
+        "subagent_system_prompt": profile.subagent_system_prompt,
+        "llm_backend": profile.llm_backend,
+        "model": profile.model,
+        "temperature": profile.temperature,
+        "top_k": profile.top_k,
+        "top_p": profile.top_p,
+        "num_thread": profile.num_thread,
+        "max_iterations": profile.max_iterations,
+        "planning_enabled": profile.planning_enabled,
+        "planning_mandatory": profile.planning_mandatory,
+        "planning_phase1_enabled": profile.planning_phase1_enabled,
+        "planning_phase2_enabled": profile.planning_phase2_enabled,
+        "planning_phase3_enabled": profile.planning_phase3_enabled,
+        "think_enabled": profile.think_enabled,
+        "iteration_budget_enabled": profile.iteration_budget_enabled,
+        "goal_anchoring_enabled": profile.goal_anchoring_enabled,
+        "goal_anchoring_interval": profile.goal_anchoring_interval,
+        "anti_stall_enabled": profile.anti_stall_enabled,
+        "anti_stall_threshold": profile.anti_stall_threshold,
+        "step_validation_enabled": profile.step_validation_enabled,
+        "adaptive_replan_enabled": profile.adaptive_replan_enabled,
+        "subagent_tools": profile.subagent_tools,
+        "subagent_planning_enabled": profile.subagent_planning_enabled,
+        "subagent_think_enabled": profile.subagent_think_enabled,
+        "enabled_tools": profile.enabled_tools,
+        "context_providers": profile.context_providers,
+        "is_admin_only": getattr(profile, "is_admin_only", False),
+    }
+
+
+@router.put("/profiles/{profile_id}")
+async def admin_update_profile(
+    profile_id: str,
+    body: dict,
+    user: Annotated[User, Depends(require_permission("navi.profiles.manage"))],
+):
+    """Update profile configuration on disk and in-memory.
+
+    Accepts a partial update — only provided fields are modified.
+    Writes config.json and system_prompt.txt back to disk.
+    """
+    from pathlib import Path
+    from navi.api.deps import get_profile_registry
+    from navi.profiles.base import AgentProfile
+    from navi.profiles.loader import save_profile_to_dir
+
+    registry = get_profile_registry()
+    try:
+        old_profile = registry.get(profile_id)
+    except Exception:
+        raise HTTPException(status_code=404, detail="Profile not found")
+
+    # Build updated profile from existing data + body overrides
+    updated_data = old_profile.model_dump()
+    updated_data.update(body)
+
+    # Preserve fields that must not change via this endpoint
+    updated_data["id"] = profile_id
+    updated_data.setdefault("name", old_profile.name)
+    updated_data.setdefault("description", old_profile.description)
+    updated_data.setdefault("enabled_tools", old_profile.enabled_tools)
+    updated_data.setdefault("system_prompt", old_profile.system_prompt)
+
+    try:
+        updated_profile = AgentProfile.model_validate(updated_data)
+    except Exception as e:
+        raise HTTPException(status_code=400, detail=f"Invalid profile data: {e}") from e
+
+    # Preserve is_admin_only (not part of base model validation)
+    if hasattr(old_profile, "is_admin_only"):
+        updated_profile.is_admin_only = old_profile.is_admin_only
+
+    # Write to disk
+    profiles_dir = Path(__file__).parent.parent.parent / "profiles"
+    save_profile_to_dir(updated_profile, profiles_dir)
+
+    # Update in-memory registry
+    registry.update(updated_profile)
+
+    log.info("admin.profile_updated", profile_id=profile_id, admin_id=user.id)
+    return {"ok": True}
diff --git a/navi/core/registry.py b/navi/core/registry.py
index 23ad6a1..6756e87 100644
--- a/navi/core/registry.py
+++ b/navi/core/registry.py
@@ -95,6 +95,12 @@
     def all(self) -> list[AgentProfile]:
         return list(self._profiles.values())
 
+    def update(self, profile: AgentProfile) -> None:
+        """Replace an existing profile in-memory."""
+        if profile.id not in self._profiles:
+            raise ProfileNotFound(profile.id)
+        self._profiles[profile.id] = profile
+
 
 class BackendRegistry:
     def __init__(self) -> None:
diff --git a/navi/profiles/loader.py b/navi/profiles/loader.py
index 823161e..1b33149 100644
--- a/navi/profiles/loader.py
+++ b/navi/profiles/loader.py
@@ -103,3 +103,64 @@
             log.error("profile.loader.error", profile_dir=entry.name, error=str(exc))
 
     return profiles
+
+
+def save_profile_to_dir(profile: AgentProfile, profiles_dir: str | Path) -> None:
+    """Write a profile back to its directory on disk.
+
+    Updates config.json and system_prompt.txt. Does not touch
+    subagent_system_prompt.txt unless the field is non-empty.
+    """
+    base = Path(profiles_dir)
+    profile_dir = base / profile.id
+    profile_dir.mkdir(parents=True, exist_ok=True)
+
+    config = {
+        "id": profile.id,
+        "name": profile.name,
+        "description": profile.description,
+        "short_description": profile.short_description,
+        "full_description": profile.full_description,
+        "llm_backend": profile.llm_backend,
+        "model": profile.model,
+        "temperature": profile.temperature,
+        "max_iterations": profile.max_iterations,
+        "top_k": profile.top_k,
+        "top_p": profile.top_p,
+        "num_thread": profile.num_thread,
+        "planning_enabled": profile.planning_enabled,
+        "planning_mandatory": profile.planning_mandatory,
+        "planning_phase1_enabled": profile.planning_phase1_enabled,
+        "planning_phase2_enabled": profile.planning_phase2_enabled,
+        "planning_phase3_enabled": profile.planning_phase3_enabled,
+        "think_enabled": profile.think_enabled,
+        "iteration_budget_enabled": profile.iteration_budget_enabled,
+        "goal_anchoring_enabled": profile.goal_anchoring_enabled,
+        "goal_anchoring_interval": profile.goal_anchoring_interval,
+        "anti_stall_enabled": profile.anti_stall_enabled,
+        "anti_stall_threshold": profile.anti_stall_threshold,
+        "step_validation_enabled": profile.step_validation_enabled,
+        "adaptive_replan_enabled": profile.adaptive_replan_enabled,
+        "subagent_tools": profile.subagent_tools,
+        "subagent_planning_enabled": profile.subagent_planning_enabled,
+        "subagent_think_enabled": profile.subagent_think_enabled,
+        "enabled_tools": profile.enabled_tools,
+        "context_providers": profile.context_providers,
+    }
+
+    config_file = profile_dir / "config.json"
+    config_file.write_text(
+        json.dumps(config, indent=2, ensure_ascii=False) + "\n",
+        encoding="utf-8",
+    )
+
+    prompt_file = profile_dir / "system_prompt.txt"
+    prompt_file.write_text(profile.system_prompt + "\n", encoding="utf-8")
+
+    subagent_file = profile_dir / "subagent_system_prompt.txt"
+    if profile.subagent_system_prompt:
+        subagent_file.write_text(profile.subagent_system_prompt + "\n", encoding="utf-8")
+    elif subagent_file.exists():
+        subagent_file.unlink()
+
+    log.info("profile.saved", profile_id=profile.id, dir=str(profile_dir))